Device for pulling the leading end of yarn from a textile coil



A ril 9, 1968 THE LEADING END OF YARN FROM A TEXTILE COIL Filed March25, 1966 H. RAASCH ETAL 3,377,031 DEVICE FOR PULLING United StatesPatent ABSTRACT OF THE DISCLOSURE Device for pulling a leading end ofyarn from a coil includes coil holder means for rotating a yarn coilabout its axis, a suction nozzle having a suction mouth adjacent theholder means to induct an air current for pulling the yarn end off therotating coil, mechanical clamping means located in the suction-aircurrent of said nozzle, and means for moving the clamping meansperiodically into engagement with the yarn end within the suction-aircurrent for supplementing the entraining action of the suction-aircurrent to grip the yarn end intermittently.

Specification Our invention relates to a device for pulling the leadingyarn end from a rotating spinning cop, cheese or other coil by meansof'a suction nozzle whose mouth is located close to the coil peripheralsurface.

It is known to seek the yarn on a spinning cop or a cheese, cone orother yarn package by placing the mouth of a suction nozzle at a slightdistance from the rotating body of yarn, so that the starting length ofyarn is sucked into the nozzle and then pulled off the yarn body or heldarrested in the nozzle by the pulling force of the suction air current.

It has been found that under particular operating conditions, the yarnmay form a number of turns or 'a bunch which is wound in the directionopposed to the winding sense of the yarn body. Such a counter windingmay come about, for example, if the yarn to be pulled off is clampedbetween individual yarn layers of the coil and is entrained by theseyarn layers during rotation of the coil. This occurs particularly incases where the suction force of the nozzle is weak or becomes weak dueto a relatively slight negative pressure-or because the spacing betweennozzle mouth and yarn body is too large. The latter event is apt tooccur, for example, with spinning cops when the nozzle is to act notonly upon the cylindrical but also upon the conical portion of the yarnbody.

It is virtually impossible to adapt the shape of the nozzle mouth tothat of the conical portion near the tip of a cop, because the positionand shape of the conical portion vary greatly even if one and the sameoutput of a spinning machine is being wound upon a multiplicity ofspinning cops. For that reason, there exists a relatively large spacingbetween the suction nozzle and the starting cone of such cops, so thatat the starting cone the pulling force of the current of suction air islower than at the cylindrical, major portion of the yarn bodyconstituted by the cop, with the result that in the vicinity of theconical portion, there may be insufficient resistance to the formationof counter windings.

It is accordingly an object of the invention to prevent the occurrenceof opposingly wound yarn turns or bunches on the body of yarn from whichthe leading end is being pulled off by suction.

It is a more specific object of our invention to reliably prevent thepossibility of counter-winding formation even if the operatingconditions are such as to normally present the danger of such formationbecause of a relatively large spacing between nozzle mouth and coil orbecause of any other circumstances apt to reduce the: suction force ofthe nozzle at a particular locality of the coil.

To this end, and in accordance with our invention, we provide the devicefor suctionally pulling the leading end of yarn from a coil with grippermeans for periodically seizing the yarn end located in the suction flowpath of the suction nozzle whose mouth is adjacent the holder meanswhich accommodates the coil of yarn and rotates it about its axis whenthe suction nozzle acts to pull the leading end of yarn from the coil.The gripper means are of such construction that when the yarn end isperiodic'ally seized or clamped thereby and as the coil continuesrotating, any catches formed in the yarn, which cause the aforementionedcounter windings, are accordingly torn away. The loosened yarn loop,present when the gripper means are released, is then entrained by thesuction flow and sucked away.

According to other features of our invention, the gripper means comprisea pair of oscillata-ble, periodically overlapping yarn-diverting memberslocated in front of the mouth of the suction nozzle. The members areformed of channels having a U-shaped profile, the legs thereof extendingtoward one another so as to intermesh, and by supplementing theentraining or clamping of the yarn produced thereby, resistance iseffected against the withdrawal of the yarn from the nozzle when acounter-winding is formed. Since the yarn can then no longer bewithdrawn from the nozzle without very great resistance, the yarn catchwhich can cause the formation of a counterwinding, is torn away as thecoil continues to rotate. The loosened loop then present can be rapidlysucked away as in the aforementioned case when the meshing yamdivertingmembers are separated from one another.

Other features which are considered as characteristic for the inventionare set forth in the appended claims.

Although the invention is illustrated and described herein as embodiedin device for pulling the lead end of yarn from a textile coil, it isnevertheless not intended to be limited to the details shown, sincevarious modifications and structural changes may be made therein withoutdeparting from the spirit of the invention and within the scope andrange of equivalents of the claims.

The construction and method of operation of the invention, however,together with additional objects and advantages thereof will be bestunderstood from the following description of a specific embodiment whenread in connection with the accompanying drawing, in which:

FIG. 1 is, by way of example, a schematic plan view of an embodiment ofa yarn-end pulling device constructed in accordance with our invention;and

FIG. 2 is a section taken along the line IIII of FIG. 1 in the directionof the arrows.

Referring now to the drawing, there is schematically shown a spinningcop 1 accommodated between two guiding abutments 2 and 3 which haverespective funnelshaped recesses for centering and clamping the cop 1 incoaxial alignment with the respective shafts of the holders 2 and 3. Theholder 3 is shown driven from a suitable drive 14. A suction nozzle 4has a mouth opening located at 4b at a small distance from theperipheral surface of the cop 1, the length of the mouth opening beingsubstantially equal to the axial length of the yarn body of the cop. Thestarting length of yarn is to be pulled off the cop 1 by the suctionproduced by the nozzle 4. It will be recognized that due to the varyingdistance between the nozzle mouth and the peripheral surface of thecoil, the suction force varies accordingly along the length of the cop.That is, in the vicinity where the yarn body is conical, namely at C inthe vicinity of the coil tip, the suction force is lower than at thecylindrical portion B. Consequently, the danger of. counter-windingformation is largest in the conical region C.

As shown in the sectional view of FIG. 2, a sheet-metal channel, 6 ofU-shaped profile is located substantially along the starting cone C ofthe spinning cop 1 at the mouth 4b of the suction nozzle 4. A rocker arm8 is mounted on the nozzle 4 and is pivotable intermediate its endsabout a pin 7. At the lower end of the rocker arm 8, as seen in FIG. 2,another sheet-metal channel '6' of U-shaped cross section is secured asby soldering, welding or any other suitable fastening means. One end ofa coupling 9 is secured as by a pivot pin to the other end of the rockerarm 8, and the free end of the coupling 9 is fastened 'to a cam disc 10which is rotated by a motor 5 through suitable transmission means thatare not'illustrated. The rocker arm 8 thus rocks back and forth so thatthe edges of the U-shaped channel 6' periodically overlap the edges ofthe U-shaped channel 6. The yarn end sucked into the nozzle 4 isconsequently seized and drawn into the channels 6 and 6'. Due to theadditional clamping of the yarn produced thereby, re-

sistance'is applied against the withdrawal of the yarn from the nozzlewhen a counter-winding is formed. Since the yarn can then no longer bewithdrawn from the nozzle without very great ellort, the yarn catch,which can cause the formation of a counter-winding, is torn away as thecoil continues rotating. When the rocker arm 8 disengages the U-shapedchannels 6 and 6', the loosened loop then present is rapidly sucked awaybefore the yarn is again clamped by the periodically overlappingyarndiverting members. It has also been found to be advantageous toprovide a drive for the rocker arm 8 which will produce oscillationsthereof at a frequency having a magnitude in the tens of the number ofrevolutions of the cop.

We claim:

1. Device for pulling a leading end of yarn from a coil, comprising coilholder means for rotating a yarn coil about its axis, a suction nozzlehaving a suction mouth adjacent said holder means to induct an aircurrent for pulling the yarn end off the rotating coil, mechanicalclamping means located in the suction-air current of said nozzle, andmeans for moving said clamping'means periodically into engagement withthe yarn end within the suction-air current for supplementing theentraining action of the suction-air current to grip the yarn endintermittently.

2. Device according to claim 1, wherein said clamping means comprises apair of yarn-diverting members mounted for oscillation relative to oneanother on said suction nozzle, said yarn-diverting members having edgesthat are periodically mutually overlapping.

3. Device according to claim 2, wherein said yarndiverting members arelocated at the mouth of said suction nozzle. 7

4. Device according to claim 2, wherein said yarndiverting members arein the form of a channel having a substantially U-shaped cross section.

5. Device according to claim 4, wherein one of said channels is fixed toan edge of said suction mouth and the other of said channels is carriedby a rocker arm and oscillatable into periodic overlapping relationshipwith said fixed channel.

References Cited UNITED STATES PATENTS 2,857,113 10/1958 Kupper 242-183,136,494 6/1964 Furst 24235.6

STANLEY N. GILREATH, Primary Examiner.

